Before anyone else offers up handgun scopes, the OP is asking for his rifle.
IMO, if you only want 4x then a 1-4x would make sense. Size and weight would be about identical. If you really want a fixed magnification then step up to a SWFA 6x
he's got a 7.62x39 which has a rainbow trajectory ......so 6X is very limiting.
low power variables are great......
just expensive & not too many come....
1 X 4 power.
my Leupold vari-X III in 1.75 X 6 is mounted on my Browning A-bolt in
7mm-08 and with it I have taken quite a few deer.
optics are great and I usually start carrying it on 1.75 and dial up as needed.
Buying a scope now is really difficult because the current ones are expensive.
the great thing to remember is a very good scope costs more than many rifles that wear them.
best of all you can tranfer them as needed & Leupold is for life....yours, mine and any one that owns it!
Was figuring on a 25/200 zero but after looking at some ballistic tables figured id try a 50 yard zero And be pretty close out to 150. Shot it today with irons since I don’t have a scope yet but a 50 yard zero had me shooting high at 200? Was shooting in the rain so I’ll have to get out on a nicer day to sort it out
Iron sights & scopes have different trajectory tables!
scopes with regular height rings are 1.5 inches above bore line.
iron sights are only 3/4"
Iron sights I use 12.5 yards to hit zero @ 100 yds. for most calibers. fine adjustment only are then needed
Same gun with scope I use 25 yards for zero @ 100 yds. again fine adjustments needed
My SKS using iron sights with Tula 154gr SP ammo sighted in at 100 yds groups about 3 inches...
I move rear sight up to 300 meter notch and I can group same ammo about 6" group at 200 yds....
that's from actual range time data and not just from a balistics table.
BTW you can learn a lot from
Jack O'Connor's The Hunting Rifle.
Found that book. Looks like the man wrote quite a bit. $35 well spent, looking forward to reading it